A mobile operator always uses a licensed frequency band for cellular access, and uses various technology innovations to improve spectrum utilization of the existing licensed spectrum. However, with development of communications technologies, pressure for expansion of a mobile broadband network becomes heavier, and a bottleneck is encountered when technology innovations are used to improve spectrum utilization of the existing licensed spectrum. In this case, mobile communications industries at home and abroad begin to consider using more spectrum resources to improve spectrum utilization. For example, using an unlicensed spectrum to perform data communication in a cellular system, that is, simultaneously using a licensed spectrum and an unlicensed spectrum to access the cellular system, so as to achieve higher access efficiency, higher reliability, and better mobility. However, in the cellular system, random access to the unlicensed spectrum easily causes interference between the licensed spectrum and the unlicensed spectrum. Therefore, how to schedule an unlicensed spectrum resource to perform data communication becomes a primary problem to be resolved.